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Recent research found that the average American's contribution to
climate change drops after age 65.

As they near retirement, Americans pump out more per capita
carbon dioxide emissions than at any time in their life,
approximately 14.9 metric tons per year, according to the study
published in the journal
Demographics. But after 65, average emissions drop until
reaching 13.1 metric tons for 80-year-olds, the greatest age for
which data was available.

These results could alter projections of future greenhouse gas
emissions.

"Emissions will continue to grow because the population size will
continue to increase. However, they will grow less than we would
have expected based only on projections of population size only,"
the study's author Emilio Zagheni of the Max Planck Institute for
Demographic Research told Discovery News.

Zagheri correlated age to greenhouse gas production by looking at
how the use of nine factors, such as air travel, gasoline and
electricity, changed as people aged.

He found that gasoline use went down as people became more
sedentary in later life, but home electricity and natural gas use
increased.

For American seniors reducing home energy costs looks like the
green choice. It could also save them some green.

"Our research confirms that utilities' costs make up a larger
share of expenses for older consumers than for younger, and we
work on several fronts to help ensure our members and all older
Americans can better afford their home energy bills," Tiffany
Lundquist, media relations manager for the AARP, formerly known
as the American Association of Retired Persons, told Discovery
News.

"In our publications, web site, and educational outreach,
environmental features are popular and we frequently highlight
tips on saving money on home energy costs," said Lundquist.

"Our members' interest in this work is demonstrated in part by
their active volunteerism in support of it. As an example, the
'Operation Energy Save' toolkit, which people can use to help
friends and neighbors conserve energy, is among the more popular
of the offerings on our volunteerism web site, Create the Good,"
Lundquist said.

Energy saving seniors may be able to reduce their carbon
footprint, but it won't solve the climate change problem.

Census results show the average age of the populations of the
United States, Europe and Japan is increasing. But this
demographic shift won't result in emissions reductions until this
century is half over.

The study suggests that until 2050, aging may actually account
for a slight increase in emissions, since people's greenhouse gas
contribution continues to increase until around age 65.

"In the longer term, as more and more people will be older than
65, emissions are expected to decrease. This is partially related
to the fact that people at older ages produce less emissions and
that a reduction of the proportion of people in the labor force
tends to slow the growth in the size of the economy, and thus
consumption and emissions," Zagheri explained to Discovery News.

Although the developed world now has a touch of gray, many
emerging economies have a youth bulge.

"Aging is expected to have the same beneficial effect in
developing countries in the long term. However, it is very likely
that the increase in affluence and the process of urbanization
and development will more than counteract the beneficial effect
of aging on carbon emissions," Zagheri said.